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Comparing Coro/Coro.pm (file contents):
Revision 1.19 by root, Sat Jul 21 03:44:06 2001 UTC vs.
Revision 1.78 by root, Wed Nov 1 01:21:21 2006 UTC

… …
14 14
15 sub some_func : Coro { 15 sub some_func : Coro {
16 # some more async code 16 # some more async code
17 } 17 }
18 18
19 yield; 19 cede;
20 20
21=head1 DESCRIPTION 21=head1 DESCRIPTION
22 22
23This module collection manages coroutines. Coroutines are similar to 23This module collection manages coroutines. Coroutines are similar to
24Threads but don't run in parallel. 24threads but don't run in parallel.
25 25
26This module is still experimental, see the BUGS section below. 26In this module, coroutines are defined as "callchain + lexical variables
27+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
28callchain, it's own set of lexicals and it's own set of perl's most
29important global variables.
27 30
28=cut 31=cut
29 32
30package Coro; 33package Coro;
31 34
35use strict;
36no warnings "uninitialized";
37
32use Coro::State; 38use Coro::State;
33 39
34use base Exporter; 40use base Exporter::;
35 41
36$VERSION = 0.09; 42our $idle; # idle coroutine
43our $main; # main coroutine
44our $current; # current coroutine
37 45
46our $VERSION = '2.1';
47
38@EXPORT = qw(async yield schedule terminate current); 48our @EXPORT = qw(async cede schedule terminate current);
39@EXPORT_OK = qw($current); 49our %EXPORT_TAGS = (
50 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
51);
52our @EXPORT_OK = @{$EXPORT_TAGS{prio}};
40 53
41{ 54{
42 use subs 'async';
43
44 my @async; 55 my @async;
56 my $init;
45 57
46 # this way of handling attributes simply is NOT scalable ;() 58 # this way of handling attributes simply is NOT scalable ;()
47 sub import { 59 sub import {
60 no strict 'refs';
61
48 Coro->export_to_level(1, @_); 62 Coro->export_to_level(1, @_);
63
49 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 64 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
50 *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { 65 *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub {
51 my ($package, $ref) = (shift, shift); 66 my ($package, $ref) = (shift, shift);
52 my @attrs; 67 my @attrs;
53 for (@_) { 68 for (@_) {
54 if ($_ eq "Coro") { 69 if ($_ eq "Coro") {
55 push @async, $ref; 70 push @async, $ref;
71 unless ($init++) {
72 eval q{
73 sub INIT {
74 &async(pop @async) while @async;
75 }
76 };
77 }
56 } else { 78 } else {
57 push @attrs, $_; 79 push @attrs, $_;
58 } 80 }
59 } 81 }
60 return $old ? $old->($package, $ref, @attrs) : @attrs; 82 return $old ? $old->($package, $ref, @attrs) : @attrs;
61 }; 83 };
62 } 84 }
63 85
64 sub INIT {
65 async pop @async while @async;
66 }
67} 86}
87
88=over 4
68 89
69=item $main 90=item $main
70 91
71This coroutine represents the main program. 92This coroutine represents the main program.
72 93
73=cut 94=cut
74 95
75our $main = new Coro; 96$main = new Coro;
76 97
77=item $current (or as function: current) 98=item $current (or as function: current)
78 99
79The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 100The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
80 101
… …
83# maybe some other module used Coro::Specific before... 104# maybe some other module used Coro::Specific before...
84if ($current) { 105if ($current) {
85 $main->{specific} = $current->{specific}; 106 $main->{specific} = $current->{specific};
86} 107}
87 108
88our $current = $main; 109$current = $main;
89 110
90sub current() { $current } 111sub current() { $current }
91 112
92=item $idle 113=item $idle
93 114
… …
95implementation prints "FATAL: deadlock detected" and exits. 116implementation prints "FATAL: deadlock detected" and exits.
96 117
97=cut 118=cut
98 119
99# should be done using priorities :( 120# should be done using priorities :(
100our $idle = new Coro sub { 121$idle = new Coro sub {
101 print STDERR "FATAL: deadlock detected\n"; 122 print STDERR "FATAL: deadlock detected\n";
102 exit(51); 123 exit(51);
103}; 124};
104 125
105# we really need priorities... 126# this coroutine is necessary because a coroutine
106my @ready; # the ready queue. hehe, rather broken ;) 127# cannot destroy itself.
128my @destroy;
129my $manager;
130$manager = new Coro sub {
131 while () {
132 # by overwriting the state object with the manager we destroy it
133 # while still being able to schedule this coroutine (in case it has
134 # been readied multiple times. this is harmless since the manager
135 # can be called as many times as neccessary and will always
136 # remove itself from the runqueue
137 while (@destroy) {
138 my $coro = pop @destroy;
139 $coro->{status} ||= [];
140 $_->ready for @{delete $coro->{join} || []};
141
142 # the next line destroys the _coro_state, but keeps the
143 # process itself intact (we basically make it a zombie
144 # process that always runs the manager thread, so it's possible
145 # to transfer() to this process).
146 $coro->{_coro_state} = $manager->{_coro_state};
147 }
148 &schedule;
149 }
150};
107 151
108# static methods. not really. 152# static methods. not really.
153
154=back
109 155
110=head2 STATIC METHODS 156=head2 STATIC METHODS
111 157
112Static methods are actually functions that operate on the current process only. 158Static methods are actually functions that operate on the current process only.
113 159
… …
122 # create a new coroutine that just prints its arguments 168 # create a new coroutine that just prints its arguments
123 async { 169 async {
124 print "@_\n"; 170 print "@_\n";
125 } 1,2,3,4; 171 } 1,2,3,4;
126 172
127The coderef you submit MUST NOT be a closure that refers to variables
128in an outer scope. This does NOT work. Pass arguments into it instead.
129
130=cut 173=cut
131 174
132sub async(&@) { 175sub async(&@) {
133 my $pid = new Coro @_; 176 my $pid = new Coro @_;
177 $manager->ready; # this ensures that the stack is cloned from the manager
134 $pid->ready; 178 $pid->ready;
135 $pid; 179 $pid;
136} 180}
137 181
138=item schedule 182=item schedule
… …
141into the ready queue, so calling this function usually means you will 185into the ready queue, so calling this function usually means you will
142never be called again. 186never be called again.
143 187
144=cut 188=cut
145 189
146my $prev;
147
148sub schedule {
149 # should be done using priorities :(
150 ($prev, $current) = ($current, shift @ready || $idle);
151 Coro::State::transfer($prev, $current);
152}
153
154=item yield 190=item cede
155 191
156Yield to other processes. This function puts the current process into the 192"Cede" to other processes. This function puts the current process into the
157ready queue and calls C<schedule>. 193ready queue and calls C<schedule>, which has the effect of giving up the
194current "timeslice" to other coroutines of the same or higher priority.
158 195
159=cut 196=cut
160 197
161sub yield {
162 $current->ready;
163 &schedule;
164}
165
166=item terminate 198=item terminate [arg...]
167 199
168Terminates the current process. 200Terminates the current process with the given status values (see L<cancel>).
169
170Future versions of this function will allow result arguments.
171 201
172=cut 202=cut
173 203
174sub terminate { 204sub terminate {
175 $current->{_results} = [@_]; 205 $current->cancel (@_);
176 &schedule;
177} 206}
178 207
179=back 208=back
180 209
181# dynamic methods 210# dynamic methods
… …
187=over 4 216=over 4
188 217
189=item new Coro \&sub [, @args...] 218=item new Coro \&sub [, @args...]
190 219
191Create a new process and return it. When the sub returns the process 220Create a new process and return it. When the sub returns the process
192automatically terminates. To start the process you must first put it into 221automatically terminates as if C<terminate> with the returned values were
222called. To make the process run you must first put it into the ready queue
193the ready queue by calling the ready method. 223by calling the ready method.
194
195The coderef you submit MUST NOT be a closure that refers to variables
196in an outer scope. This does NOT work. Pass arguments into it instead.
197 224
198=cut 225=cut
199 226
200sub _newcoro { 227sub _newcoro {
201 terminate &{+shift}; 228 terminate &{+shift};
… …
208 }, $class; 235 }, $class;
209} 236}
210 237
211=item $process->ready 238=item $process->ready
212 239
213Put the current process into the ready queue. 240Put the given process into the ready queue.
214 241
215=cut 242=cut
216 243
217sub ready { 244=item $process->cancel (arg...)
218 push @ready, $_[0]; 245
246Temrinates the given process and makes it return the given arguments as
247status (default: the empty list).
248
249=cut
250
251sub cancel {
252 my $self = shift;
253 $self->{status} = [@_];
254 push @destroy, $self;
255 $manager->ready;
256 &schedule if $current == $self;
257}
258
259=item $process->join
260
261Wait until the coroutine terminates and return any values given to the
262C<terminate> or C<cancel> functions. C<join> can be called multiple times
263from multiple processes.
264
265=cut
266
267sub join {
268 my $self = shift;
269 unless ($self->{status}) {
270 push @{$self->{join}}, $current;
271 &schedule;
272 }
273 wantarray ? @{$self->{status}} : $self->{status}[0];
274}
275
276=item $oldprio = $process->prio($newprio)
277
278Sets (or gets, if the argument is missing) the priority of the
279process. Higher priority processes get run before lower priority
280processes. Priorities are small signed integers (currently -4 .. +3),
281that you can refer to using PRIO_xxx constants (use the import tag :prio
282to get then):
283
284 PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
285 3 > 1 > 0 > -1 > -3 > -4
286
287 # set priority to HIGH
288 current->prio(PRIO_HIGH);
289
290The idle coroutine ($Coro::idle) always has a lower priority than any
291existing coroutine.
292
293Changing the priority of the current process will take effect immediately,
294but changing the priority of processes in the ready queue (but not
295running) will only take effect after the next schedule (of that
296process). This is a bug that will be fixed in some future version.
297
298=cut
299
300sub prio {
301 my $old = $_[0]{prio};
302 $_[0]{prio} = $_[1] if @_ > 1;
303 $old;
304}
305
306=item $newprio = $process->nice($change)
307
308Similar to C<prio>, but subtract the given value from the priority (i.e.
309higher values mean lower priority, just as in unix).
310
311=cut
312
313sub nice {
314 $_[0]{prio} -= $_[1];
315}
316
317=item $olddesc = $process->desc($newdesc)
318
319Sets (or gets in case the argument is missing) the description for this
320process. This is just a free-form string you can associate with a process.
321
322=cut
323
324sub desc {
325 my $old = $_[0]{desc};
326 $_[0]{desc} = $_[1] if @_ > 1;
327 $old;
219} 328}
220 329
221=back 330=back
222 331
223=cut 332=cut
224 333
2251; 3341;
226 335
227=head1 BUGS/LIMITATIONS 336=head1 BUGS/LIMITATIONS
228 337
229 - could be faster, especially when the core would introduce special 338 - you must make very sure that no coro is still active on global
230 support for coroutines (like it does for threads). 339 destruction. very bad things might happen otherwise (usually segfaults).
231 - there is still a memleak on coroutine termination that I could not 340
232 identify. Could be as small as a single SV.
233 - this module is not well-tested.
234 - if variables or arguments "disappear" (become undef) or become
235 corrupted please contact the author so he cen iron out the
236 remaining bugs.
237 - this module is not thread-safe. You must only ever use this module from 341 - this module is not thread-safe. You should only ever use this module
238 the same thread (this requirement might be loosened in the future to 342 from the same thread (this requirement might be losened in the future
239 allow per-thread schedulers, but Coro::Satte does not yet allow this). 343 to allow per-thread schedulers, but Coro::State does not yet allow
344 this).
240 345
241=head1 SEE ALSO 346=head1 SEE ALSO
242 347
243L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 348Support/Utility: L<Coro::Cont>, L<Coro::Specific>, L<Coro::State>, L<Coro::Util>.
244L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. 349
350Locking/IPC: L<Coro::Signal>, L<Coro::Channel>, L<Coro::Semaphore>, L<Coro::SemaphoreSet>, L<Coro::RWLock>.
351
352Event/IO: L<Coro::Timer>, L<Coro::Event>, L<Coro::Handle>, L<Coro::Socket>, L<Coro::Select>.
353
354Embedding: L<Coro:MakeMaker>
245 355
246=head1 AUTHOR 356=head1 AUTHOR
247 357
248 Marc Lehmann <pcg@goof.com> 358 Marc Lehmann <schmorp@schmorp.de>
249 http://www.goof.com/pcg/marc/ 359 http://home.schmorp.de/
250 360
251=cut 361=cut
252 362

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